By Brenda Enos, CHMM, REM
Like automobiles moving along a highway, aircraft crisscross the sky, connecting airports in an elaborate, well-timed dance. But all that traffic in the sky is reflective of traffic on the ground, and as capacities at airports grow and skyways become more crowded, the environmental concerns associated with airport noise continue to increase.
Capacity, in terms of arriving and departing flights, depends on several variables. The number of runways in use, the types of aircraft accommodated, and the distance between departing and arriving aircraft all play a role. Delays occur when aircraft traffic exceeds an airport’s capabilities. To counter these delays, airports often use runway expansions or traffic pattern adjustments.
However, both strategies impact the surrounding areas. One of the biggest impacts is that of noise pollution, which commonly affects the areas beyond the ends of the runways, where arriving and departing aircraft fly at low altitudes. Because many of these high-noise areas surrounding airports are occupied by residential neighborhoods, the Federal Aviation Administration (FAA) enforces noise compatibility requirements for airports.
Although airlines are now using quieter aircraft, the issue of noise is as prevalent as ever. To address noise compatibility issues, many airports are performing FAA Airport Noise Compatibility Planning (Part 150) studies, which provide airport operators with guidelines for voluntary noise abatement standards.
Noise abatement procedures that result from a Part 150 study often have a negative effect on capacity. Airports experiencing both capacity and noise issues usually find that a solution to one often aggravates the other. For instance, an ideal runway configuration could direct traffic over a residential neighborhood, which typically increases noise complaints. Conversely, trying to enforce noise abatement procedures might result in unacceptable delays at peak hours.
It’s clear that there is no easy trade-off between capacity and addressing noise compliance issues. In many cases, an airport must weigh the economic value of extending or adding a runway against the environmental issues it could cause. While the answer isn’t always apparent, continued capacity growth will make such evaluations a necessity in the coming years.